SECTION 3: CLEARANCES TO COMBUSTIBLES
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SECTION 3: CLEARANCES TO COMBUSTIBLES
3.1 Required Clearances to Combustibles
Clearances are the required distances that
combustible objects must be away from the heater to
prevent serious fire hazards. Combustibles are
materials, that may catch on fire and include common
items such as wood, paper, rubber, fabric, etc.
Maintain clearances to combustibles at all times
for safety.
Clearances for all heater models are located on the
burner of the heater and on Page 5, Figure 3 through
Page 8, Figure 12 in this manual. Check the
clearances on each burner for the model heater
being installed to make sure the product is suitable
for your application and the clearances are
maintained. Read and follow the safety guidelines
below:
• Keep gasoline or other combustible materials
including flammable objects, liquids, dust or
vapors away from this heater or any other
appliance
• The stated clearance to combustible represents a
surface temperature of 90° F (50°C) above room
temperature. Building materials with a low heat
tolerance (su
ch as plastics, vinyl siding, can-
vas,triply, etc.) may be subject to degradation at
lower temperatures. It is the installer’s responsibil-
ity to assure that adjacent materials are protected
from degradation.
• Maintain clearances from heat sensitive
equipment and workstations.
• Maintain clearances from vehicles parked below
the heater.
• Maintain clearances from swinging and overhead
doors, overhead cranes, vehicle lifts, partitions,
storage racks, hoists, building construction, etc.
• In locations used for the storage of combustible
materials, signs must be posted to specify the
maximum permissible stacking height to maintain
required clearances from the heater to the
combustibles. Signs must be posted adjacent to
the heater thermostat. In the absence of a
thermostat, signs must be posted in a
conspicuous location.
• Consult local Fire Marshal, Fire Insurance Carrier
or other authorities for approval of proposed
installation when there is a possibility of exposure
to combustible airborne materials or vapors.
• Hang heater in accordance to the minimum sus-
pension requirements
on Page 13, Figure 14.
• If the radiant tubes must pass through the building
structure, be sure that adequate sleeving and fire
stop is installed to prevent scorching and/or fire
hazard.
NOTE: 1. All dimensions are from the surfaces of all tubes, couplings and elbows.
2. Clearances B, C and D can be reduced by 50% after 25' (7.5 m) of tubing downstream
from where the burner and burner tube connect.
WARNING
Fire Hazard
Keep all flammable objects, liquids and
vapors the minimum required clearances to
combustibles away from heater.
Some objects will catch fire or explode when
placed close to heater.
Failure to follow these instructions can result
in death, injury or property damage.
FIGURE 3: STANDARD REFLECTOR
(inches) (centimeters)
Model A B C D A B C D
CTH3-80 6 38 66 38 16 97 168 97
CTH3-115 6 46 77 46 16 117 196 117
CTH3-150 6 50 80 50 16 127 204 127
CTH3-200 8 52 82 52 21 133 209 133